The findings by Switzerland's Institute of Radiation Physics were inconclusive, but revived speculation that Arafat was poisoned.
The legendary Palestinian leader died Nov. 11, 2004 in a French military hospital, a month after falling violently ill at his government compound in the West Bank town of Ramallah.
The Swiss institute has said it would need to examine Arafat's remains for conclusive findings, though a clear-cut outcome is not assured because of the decay of the substance, polonium-210, over the years. Last week, Abbas said he was willing, in principle, to allow an autopsy, provided he receives permission from religious authorities and Arafat's family.
Arafat was buried in a mausoleum that has become the centerpiece of the Ramallah compound where Abbas's headquarters are located. The exhumation would create a huge spectacle that could upset some devout Muslims, though there seems to be a widespread desire among Palestinians to determine the cause of death.
Abbas aide Saeb Erekat said Monday that the Palestinian president has decided to invite the Swiss experts to Ramallah in order to examine the remains. "We are on the way to an autopsy," Erekat told The Associated Press.
Erekat said a Palestinian medical expert would contact the Swiss institute later Monday or Tuesday to offer the invitation. Erekat said an autopsy could be conducted as soon as the Swiss team arrives. There was no immediate comment from the institute.
Arafat's widow, Suha, has repeatedly called for exhuming the remains. She worked closely with the Arab satellite TV station Al-Jazeera, which conducted an investigation into Arafat's death and received permission from her to submit her husband's belongings for testing. The top Muslim cleric in the Palestinian territories has also given his blessing to exhuming the remains.
However, Arafat's nephew, Nasser al-Kidwa, has been cool to the idea of an autopsy but signaled he will not stand in the way.
"Our belief was always that it was an unusual death, and most likely he (Arafat) was poisoned. Now all indications say he was poisoned," al-Kidwa told AP.
It was not immediately clear whether al-Kidwa would or could block attempts to exhume the remains. Al-Kidwa, a former Palestinian envoy to the United Nations, heads the Yasser Arafat Foundation and is the custodian of Arafat's memory.
Erekat suggested that Abbas was firm in his decision to move forward.
